Addition and subtraction within 20 - Subtraction crossing 10 counting back - Planning

In this Year 1 mathematics lesson, the objective is to master the skill of subtraction, particularly when it involves crossing the number 10. The session starts with a small step that reviews prior knowledge through a series of 'fluent in four' questions. The class then delves into the concept of 'counting back' to subtract, using a number line as a visual aid. Key vocabulary such as 'count back', 'subtract', and 'how many left?' is introduced, with resources available online for further clarification. The teaching input involves explaining the process of crossing the number 10 on a number line and is supported by teaching slides.

Differentiated worksheets and number lines are provided to facilitate independent learning. In the first activity, children engage with a word problem that requires them to determine the number of sweets remaining after some are eaten, reinforcing the subtraction process. The lesson ensures that children understand the importance of not including the starting number when counting back their 'hops' or 'jumps' on the number line. As they gain confidence, they move on to more complex calculations, always starting at a given number and counting back to find the solution. The plenary session includes a reflective 'Give me five' activity where children articulate what they've learned, the skills they've used, what they found challenging, what aids helped them during the lesson, and what they promise to remember for future lessons. The worksheets are designed to cater to different levels of proficiency, from those needing a starting clue on their number line to those who are secure enough to perform subtraction without visual aids.